Steering, brake and suspension hints and tips from KWE

Chris Dace

12 months ago

To determine if your steering system is worn you can do the following:

When you are driving at slow speed (15mph) on a flat road, if when turning the steering wheel to change direction of the car it takes more than ½ inch movement of the steering wheel rim, then it is likely to be worn. Most worn cars will need over 2 inches at the rim to change direction.

Listen for a grinding noise from the steering pump when on full lock – if there is, then the system is leaking oil and the pump is running dry.

Observe if the car drifts left or right whilst driving. A mild drift to the right is ok on UK roads (i.e. out of the left gutter), but anything significant, or drift to the left can indicate either:

unequal tyre pressures

uneven tyre wear

different tyre types

incorrectly-setup suspension geometry

If you notice the direction of the car is unstable, either drifting or pulling left or right depending on road surface, then the toe-in could be badly out.

If the tread blocks show feathering on leading or trailing edges then the toe-in could be slightly out.

If you notice a wobble when driving at varying speeds (this tends to occur over a narrow speed range of, say, 50 – 60mph), this can indicate an unbalanced or bent wheel rim, or an unevenly worn tyre. Cheap tyres can be very bad from new. Do not confuse this wobble with brake shudder – see below.

To determine if your brakes are faulty do the following:

When gently applying the brakes, you notice that the car pulls left or right then:

there could be different brake retardation between left and right brake discs/pads

the tyres could have uneven grip

If the car wobbles when the footbrake is applied then most likely one or both front brake discs is unevenly surfaced or unbalanced.

When firmly applying the brakes on a dry road:

on ABS-equipped cars) you should feel the car judder violently as the ABS alternately skids and releases the brakes.

on non-ABS cars, at least one front wheel should lock-up and skid.

If it is not possible to make the wheels skid on a dry road then the overall brake efficiency is down, usually because one or more brake caliper piston is seized.

When stationary on a flat road or driveway with engine running, apply the handbrake, engage D (this does not work for manual gearbox cars) and release the footbrake. The car should not move forward. This is particularly relevant to the XJ or XJS with inboard brakes where the handbrake mechanism is feeble and is commonly damaged by drivers leaving the fly-off handbrake applied while driving.

To determine if there are suspension problems:

Note any rattles at the front when going over rough roads – this is usually due to worn-out damper mountings, or, less frequently, worn-out anti-roll bar mountings.

Push down on the middle of the front bumper firmly with your knee. The car should be difficult to move downwards, and it should not bounce as it rises again. Repeat at the rear. If the car bounces (i.e. more than one movement after releasing the down pressure) then the dampers are worn; if the car is easy to push down then the springs are weak.

Look at the car on a level road from the side. The car should be more or less level, with perhaps a mild nose-down attitude. If it is high at the front then the rear springs are weak – this is common.

With the car settled on a flat road or driveway, you should be able to insert two fingers between the wheel arch and the top of the tyre. If this is not possible then the: